Variable capacity store for elongated articles

ABSTRACT

A variable capacity storage unit is disclosed comprising a set of independent conveyor belts superpositioned on top of each other and connected to operate as a single storage unit. The conveyor belts are arranged in a generally H-shaped pattern including two parallel elongated portions and a transverse portion, which is movable along the elongated portions, and include a transfer belt for converting the active portions of each of the conveyor belts into a single unit.

TECHNICAL FIELD

The present invention relates to a variable capacity store for elongatedarticles. In particular the invention relates to a variable capacitystore of the FIFO type, where goods stored in the reservoir leave thestore in the same order as they were introduced. Furthermore theinvention relates to the type of variable capacity store which includesan endless conveyer being subdivided into an active path, which iscapable of transporting goods and a passive path functioning as a storefor the endless conveyor. In this type of variable capacity stores, thecapacity is altered by changing the length of the active path byremoving part of the active path from the passive path or by introducingpart of the passive path into the active path.

BACKGROUND ART

A variable capacity store for elongated articles where an endlessconveyor is subdivided into an active path and a passive path ispreviously known from EP 738478. EP 738478 discloses a variable-capacitystore for elongated articles. The store comprises an input station andan output station located in series along a path along which elongatedarticles are fed. The articles are fed by a single endless conveyor,which is subdivided into an active path and a passive path. The activepath extends from the input station to the output station and thepassive path extends from the output station to the input station. Theactive path is formed by a part of the endless conveyer, which is woundaround a first set of drums in a first spiral. The passive path, orreturn branch, is formed by a part of the endless conveyor, which iswound around a second set of drums in a second spiral.

A drawback of the variable capacity store of the above type is that thetransfer between the active path and passive path is performed at asingle point, which is where the endless conveyer leaves the firstspiral to enter the second spiral or vice versa, in dependence ofwhether the active path should be lengthened or shortened. The frictionbetween the drums and the endless conveyor will increase as the numberof turns increases from the point of entrance where the active andpassive paths are connected. This implies that, when trying to changethe division between the active path and passive path, by removing partof the active path from the passive path or by introducing part of thepassive path into the active path, the tension of the chain willincrease from the point of entrance where the active and passive pathsare connected as the number of turns increases. When a reservoir is usedin a process which has relatively large short term variations in thecapacity of a delivering device, which is arranged to feed thereservoir, and a receiving device, which is arranged to be fed by thereservoir, it is of importance that the capacity of the reservoir can bealtered quickly. A limiting factor in this regard, is that the endlessconveyor is designed to support a maximum tension. The tension in theendless conveyor is dependent on the velocity of the change of length ofthe active and passive path. Since the tension in the endless conveyorincreases as the number or turns increases, the maximum feed in-feed orfeed out velocity from the active path will be determined from thetension in the chain at the last turn, calculated from the point ofentrance. For a conveyor of a determined rigidity, there will be amaximum number of turns allowed for a specific maximum feed in-feed orfeed out velocity from the active path. If the designer would need moreturns in order to create a larger variable capacity store, the designerwould have to contemplate to make a more rigid conveyor, which in turnwould increase the weight of the chain and thus require a completeredesign of the store.

DISCLOSURE OF INVENTION

One object of the invention is to provide a variable capacity store inwhich allow a freedom in design of the number of layers in an activepath without a corresponding increase in tension of the chain as thenumber of turns increases, such that the response to short termvariations cab be quick even for relatively large stores comprising aplurality of turns in the active path.

This object is achieved by a variable capacity store according to thecharacterising portion of claim 1. The invention relates to a variablecapacity store comprising a set of conveyor means superpositioned on topof and connected to each other. Since a number of conveyor means aresuperpositioned on top of each other, the capacity of the store can bedesigned by deciding how many layers should be used. Since each layerworks independently from the other layers of the store, the addition ofa layer does not alter the design of the layers already present in thestore. This type of store can therefore be redesigned in order to meetchanged requirements of capacity only by adding a layer and replacingthe input or output station of the store, depending on which side theadditional layer is positioned. The other parts of the store do not needto be altered. Each layer is formed by a conveyor means.

The invention makes use of conveyor means includes an endless conveyorbeing arranged in a generally H-shaped pattern including two parallelelongated portions and a transverse portion, which is movable along saidelongated portions. The H-shaped pattern is, by said transverse portion,divided into an active path positioned one side of the transverseportion and a passive path positioned on the other side, wherein thecapacity of the conveyor means is arranged to be varied by displacingthe transverse portion and thereby increasing or decreasing theproportion between the active path and passive path.

Since the layers are formed by essentially a single endless conveyor,the tension in an endless conveyer in one layer will be independent ofthe tension in an endless conveyer in another layer. It is thereforepossible to arrange a store with a multiplicity of layers without acorresponding increase in tension of the chain as the number of layersincreases, such that the response to short term variations cab be quickeven for relatively large stores comprising a plurality of layers.

The H-shaped endless conveyors are connected to each other by transfermeans arranged between said active paths of conveyor means. The transfermeans is preferably formed by a curved conveyor path extending from anend of an elongated portion on one side of a first generally H-shapedendless conveyor toward an end of an elongated portion on the oppositeside of a second generally H-shaped endless conveyor positioned on topof said first generally H-shaped endless conveyor.

In a still further preferred embodiment the curved conveyor path isformed by an extension of the generally H-shaped endless conveyor in oneor both of two interconnected conveyor means superpositioned on top ofand connected to each other.

In yet another preferred embodiment of the invention each transverseportion in the set of conveyor means is individually displaceable alongthe elongated portions of the H-shaped conveyor means, such that thecapacity of each conveyor means in said set of conveyor means iscontrolled independently from the capacity of other conveyor means insaid set. This embodiment is particularly advantageous since even if thedrive for change of position of the transverse portion is stuck orbecomes inoperative for some other reason, the capacity of the storewill be variable, due to the variation of the capacity of the remaininglayers.

The invention also relates to a variable store arrangement comprising afirst and a second variable capacity store as described above. Accordingto this embodiment the active paths together with the transfer means ofthe first variable capacity store forms a first conveyor path which isarranged to perform transportation of goods from one conveyor means tothe next conveyor means in said set of conveyor means in a firstdirection. Furthermore, the active paths together with the transfermeans of the second variable capacity store forms a second conveyor pathwhich is arranged to perform transportation of goods from one conveyormeans to the next conveyor means in said set of conveyor means in asecond direction opposite to said first direction.

In the embodiment, the active paths together with the transfer means ofthe second variable capacity store forms a second conveyor path which isarranged to perform transportation of goods from one conveyor means tothe next conveyor means in said set of conveyor means in a seconddirection opposite to said first direction.

The elongated portions of the second variable capacity store arepositioned between the elongated portions of the first variable capacitystore and the transfer means of the second variable capacity store ispositioned between the transfer means and the transverse portion of thesecond variable capacity store, whereby the first conveyor path isessentially circumventing the second transportation path.

A variable store arrangement arranged as indicated above provides isvery compact, by which is meant that a large amount of goods can bestored on a relatively small area, furthermore, the input and output tothe store arrangement can be arranged at approximately the same height.This is an advantage, if a production in a factory is done inessentially a single plane. In this case, the need for a lift or adowndrop, which normally would follow a variable capacity store wherethe input and output is arranged at different heights is removed.

Preferably, the generally H-shaped patterns of said first variablecapacity store is vertically displaced from said generally H-shapedpatterns of said second variable capacity store. By this arrangement,the transverse portions of respective first and second variable capacitystore is prevented from colliding with each other.

BRIEF DESCRIPTION OF DRAWINGS

Embodiments of the invention will be described in detail below, withreferences to the appended drawings, where:

FIG. 1 shows a top view of a conveyor means including an endlessconveyor being arranged in a generally H-shaped pattern.

FIG. 2 shows a view form below of the conveyor shown in FIG. 1.

FIG. 3 shows a side view of a conveyor means including a drive means fora support for the transverse portion of the H-shaped conveyor means.

FIG. 4 shows a top view of the conveyor in FIG. 1, where the transverseportion is moved to an end position, wherein the storage capacity is ata minimum for the store and a first embodiment of transfer means fortransferring gods from one layer to another layer in the set of H-shapedendless conveyors stacked on top of each other.

FIG. 5 shows an end view of a set of H-shaped conveyers stacked on topof each other, where transfer means are arranged to transfer the goodsfrom one layer to another.

FIG. 7 shows a second embodiment of transfer means.

FIG. 8 shows a third embodiment of transfer means.

FIG. 9 shows a top view of an embodiment of a variable store, includingan inner and an outer variable capacity store, where both variablecapacity stores are full,

FIG. 10 show a perspective view of the outer variable store only,

FIG. 11 show a perspective view of the inner variable store only,

FIG. 12 shows a top view of an embodiment of a variable store, includingan inner and an outer variable capacity store, where the outer variablecapacity store is full and the inner variable capacity store is halffull,

FIG. 13 shows a top view of an embodiment of a variable store, includingan inner and an outer variable capacity store, where the outer variablecapacity store is full and the inner variable capacity store is empty,

FIG. 14 shows a top view of an embodiment of a variable store, includingan inner and an outer variable capacity store, where the outer variablecapacity store and the inner variable capacity store are empty,

FIG. 15 shows a perspective view of an embodiment of a variable storearrangement including an inner and an outer variable capacity store.

MODE(S) FOR CARRYING OUT THE INVENTION

In FIG. 1 a top view of a conveyor means 1 is shown. The conveyor means1 is intended to be used in a variable capacity store including aplurality of layers, each including a conveyor means 1, superimposed ontop of each other. The conveyor means 1 includes an endless conveyor 2being arranged in a generally H-shaped pattern including two parallelelongated 3, 4 portions and a transverse portion 5. The endless conveyor2 rests on a frame 6. The frame includes a first and a second parallelsupport rails 7,8 and a transverse support bar 9. The parallel supportrails 7,8 are arranged to support the parallel elongated portions 3, 4of the endless conveyor and the support bar 9 is arranged to support thetransverse portion 5.

The transverse support bar 5 is movably arranged along the length of theparallel support rails 7,8. By movement of the transverse support bar 9,the position of the transverse portion of the endless conveyer 2 will bealtered. Movement of the transverse support bar 9 is accomplished by adrive motor 10 (FIG. 3), which engages a guide bar 11 extending in thesame direction as the support rails 7,8. The transverse support 9 bar isslidably arranged in the support rails 7,8 by engagement of a notch (notshown) in a longitudinally extending groove 12 (FIG. 3) in a sideportion of the support rail 7,8. In order to limit the movement of thetransverse support bar 9 end stops 16, 17 can be provided at respectiveend of the guide bar 11.

The endless conveyor 2 is by said transverse portion 5, divided into anactive path A positioned one side of the transverse portion and apassive path P positioned on the other side. The endless conveyor 2enters at a first end 20 of the first support rail, where, according tothe embodiment shown in FIG. 1, the conveyer 2 is flexed, from runningon the bottom side 14 of the first support rail 7, to run in theopposite direction on the top side 13 of the first support rail 7. Theconveyer 2 runs toward the transverse support bar 9, which supports acurved transverse portion 21 of the conveyer 2. The curved transverseportion 21 of the conveyer 2 can be arranged in a manner known to theskilled in the art, for example via a curved track or by locally flexingthe conveyers at the ends of the transverse support bar 9. The conveyerleaves the transverse support bar 9 to be supported by the secondsupport rail 8.

The conveyer further extends toward a first end 22 of the second supportrail 8, where the conveyer 2 is flexed from running on the top side 13of the second support rail 8 to run in the opposite direction on thebottom side 14 of the second support rail 8. The conveyer further runson the bottom side 14 of the second support rail 8 toward a second endportion 23 of the second support rail 8, where the conveyer 2 is flexed,from running on the bottom side 14 of the second support rail 8, to runin the opposite direction on the top side 13 of the second support rail8. The conveyer 2 further runs toward the transverse support bar 9,where a flexed transverse portion 24 of the conveyer 2, which isincluded in the passive path P, it is flexed toward the first supportrail 7. The flexed transverse portion 24 of the conveyer 2 can bearranged in a manner known to the skilled in the art, for example bylocally flexing the conveyers by roller wheels 25, 26 at the ends of thetransverse support bar 9 as shown in the embodiment shown in FIG. 1 orvia a curved track. Leaving the flexed transverse portion 24, theconveyer 2 further extends toward a second end 27 of the first supportrail 7. At the second end 27 of the first support rail, the conveyer isflexed from running on the top side 13 of the first support rail 7 torun in the opposite direction on the bottom side 14 of the first supportrail 7. The conveyer further runs on the bottom side 14 of the firstsupport rail 7 toward the first end portion 20 of the first support rail7, where the conveyer 2 is flexed, from running on the bottom side 14 ofthe first support rail 7, to run in the opposite direction on the topside 13 of the first support rail 7, where it first entered.

The transverse support bar supports the curved transverse portion 21 andthe flexed transverse portion 24 of the conveyer. The active path Aincludes the portion of the conveyor 2 extending from the first end 20of the first support rail 7 to the first end 22 of the second conveyer8. The active path A also includes the curved transverse portion 21.Furthermore the active path A includes transfer means 19 (FIGS. 4–7)connecting active paths of conveyor means of different layers ofconveyor means.

The passive path P includes the portions 28, 29 (FIG. 2) of the conveyor2 which extends along the bottom side 14 of the first and second supportrails 7,8. Furthermore, the passive path P includes the portion of theconveyor which extends from the second end 23 of the second support rail8 to the second end 27 of the first support rail 7. This portionincludes the flexed portion 24, which is carried by the transversesupport bar.

By changing the position of the transverse support bar 9 along thesupport rails 7,8, the relative proportion between the active path A andpassive path P is changed.

In FIG. 2, the conveyer means shown in FIG. 1 is shown from a viewbelow. The bottom side 14 of the first and second support rails 7,8carries portions 28, 29 of the conveyer, which form part of the passivepath P. Furthermore the guide bar 11 extending along the length of thesupport rails 7,8 is shown. The bottom side of the transverse supportbar 9 carries a drive motor 15 for changing the position of thetransverse support bar 9 via engagement to a guide bar 11.

In FIG. 4 a top view of the conveyor in FIG. 1 is shown, where thetransverse support bar 9 is moved to an end position E, wherein thestorage capacity is at a minimum for the store. Furthermore a firstembodiment of transfer means 19 for transferring goods from one layer toanother layer in the set of H-shaped endless conveyors stacked on top ofeach other is attached at an end 30 of the conveyer means 1 on which theactive path A is situated. In the shown embodiment the transfer means 19is formed by a separate curved conveyor, which preferably is arranged asan endless conveyor. The transfer means 19 is attached to outgoingportion of the endless conveyor 2 where, that is at the first end 22 ofthe second support rail 8, where a transfer from the active path A onthe top side 13 of the second support rail 8 to the passive path P onthe bottom side 14 occurs. The transfer means, which is included in theactive path A, lead toward the first end 20′ of the first support rail7′ of a conveyer means 1′postioned on top of the conveyer means 1 shownin FIG. 4.

In FIG. 5 an end view of a set of conveyer means, including a first-1, asecond-1′, a third 1″ and a fourth-1′″ conveyor means, which arepositioned on top of each other are shown. A first, second and thirdtransfer means 19, 19′, 19″ are arranged for connecting the active pathsA, A′, A″, A′″ of respective conveyer means.

In FIG. 6 a first alternative embodiment of the transfer means 19 isshown. Here the second support rail 8 is extended and comprises a curvedportion 31. The curved portion 31 is also inclined upwards in a verticaldirection such that it connects the incoming end 20′ of the firstsupport rail 7′ in a conveyor means 1′ positioned on top of the conveyormeans 1, which carries the curved portion. The first end 22 of thesecond support rail is adjoined to the first end 20′ of the firstsupport 7′ of the conveyor means 1′ such that a transfer from a firstconveyor means 1 to a second conveyor means 1′ positioned on top of saidfirst conveyor means is possible.

Instead of extending the second support rail 8 it is possible to prolongthe first support rail. In this case the first support rail 7′ of thesecond conveyer means 1′ would be extended and would comprise a curvedportion. The curved portion would be inclined downwards in a verticaldirection such that it connects the outgoing end 22 of the secondsupport rail 8 in a conveyor means 1 positioned below the conveyor means1′, which carries the curved portion.

FIG. 7 show a third embodiment of the transfer means 19. According tothis embodiment both the first guide rail 7′ of a second conveyer means1′ and the second guide rail 8 of the first conveyor means are extendedto include curved portions 32, 33. The curved portions are positionedsuch that the connect each other such that transfer between respectiveconveyor means are possible.

According to the invention the transfer means can be either formed asseparate means such as shown in FIG. 4 or by extension of the firstguide rail, the second guide rail or both the first and second guiderail in a manner so as to connect the outgoing end of a conveyor meanswith an incoming end in another conveyor means positioned on top. Anincoming end is an edge portion of a conveyor means where an endlessconveyor flexes from the bottom off a guide rail to the top of the guiderail at a position where the conveyor on the topside is running from theedge.

FIG. 8 shows a variable capacity store 34 according to the invention inuse as a variable capacity store for elongated articles. The store isfed with elongated articles, in particular tobacco products from amanufacturing unit 35. The elongated articles are elevated by anelevator unit 35′ to the top level of the variable capacity store 34.The elongated articles enters the variable capacity store 34 at an inputtrack 36, which in this example is positioned at the highest conveyormeans 37″ in a set of three conveyer means 37–37″. In a preferredembodiment of the invention, the transverse portions 38–38″in said setof conveyor means 37–37″ is individually displaceable along saidelongated portion, such that the capacity of each conveyor means in saidset of conveyor means is controlled independently from the capacity ofother conveyor means in said set. In the example shown the lowestconveyor is positioned such that the active path is as large aspossible, while the two remaining transverse portions are positionedmidways. Naturally, the invention also contemplates the possibility torun the transverse portions in pairs or altogether fixed together forsimultaneous movement. However, according to the most preferredembodiment the transverse portions are individually moveable for maximumflexibility of the storage capacity.

The positions of the transverse portions 38–38″ are controlled by driveunits connected to guide rails as explained in connection with FIG. 3.Respective endless conveyor are driven by a single drive unit (notshown) or by a single drive unit which is connected to respectiveendless conveyer by a transmission.

The goods leave the variable capacity store at an output station 39,which in the shown example is positioned at the bottom of the variablecapacity store. From the output station the goods enters a packingmachine 40.

In FIG. 9 a top view of an embodiment of a variable store, including aninner variable capacity store 100 and an outer variable capacity store101 is shown. In FIG. 10 it is shown how the active paths 102, 102′,102″ together with the transfer means 103,103′, 103″ of the first outervariable capacity store 101 forms a first conveyor path 104. The firsttransport path 104 is arranged to perform transportation of goods fromone conveyor means 105 to the next conveyor means 105′ etc. in a set(105–105″) of conveyor means in a first direction indicated with arrow106 in an upward route of track. Each transport means (105–105″) and thetransfer means 103, 103′, 103″ between the transport means are arrangedin the manner described above. The set (105–105″) of conveyor meansincludes an infeed track 107, where goods are delivered to the variablecapacity store, and an exit path 108, which leads to an inner variablecapacity store 100.

In FIG. 11 it is shown how the active paths 109, 109′ 109″ together withthe transfer means 110, 110′, 110″ of the second inner variable capacitystore 100 forms a second conveyor path 111. The second conveyor path 111is arranged to perform transportation of goods from one conveyor means112″ to the next conveyor means 112′ in a set of conveyor means(112–112″) in a second direction opposite to said first direction in adownward route of track. The second direction is indicated with an arrow113. Each transport means (112–112″) and the transfer means110,110′,110″ between the transport means are arranged in the mannerdescribed above. The set (112–112″) of conveyor means includes an infeedtrack 114 which receives from the outer variable capacity store 101 andan exit track 1 15, where goods are delivered from the variable capacitystore.

The first outer variable capacity store includes elongated portions 116,117. The second inner variable capacity store includes similar elongatedportions 118 , 119. The elongated portions 118, 119 of the second innervariable capacity store 100 are positioned between the elongatedportions 116, 117 of the first variable capacity store 101.

Furthermore the transfer means 110 of the second inner variable capacitystore 101 is positioned between the transfer means 103 and thetransverse portions 120–120″ of the first outer 101 variable capacitystore.

The first conveyor path is thus essentially circumventing the secondtransportation path.

FIGS. 12–14 show a top view of an embodiment of a variable store,including an inner and an outer variable capacity store, where the innerand outer capacity stores are filled to different levels.

FIG. 15 show a perspective view of a variable store, including an innerand an outer variable capacity store.

FIGS. 12–15 includes the same features as explained in relation to FIGS.9–11 and will therefore not be described in full detail.

The invention shall not be restricted to the embodiments describedabove, but can be varied within the scope of the appended claims.

1. A variable capacity storage unit comprising a plurality ofindependent conveyor means connected to operate as a single storageunit, each of said plurality of conveyor means comprising an endlessconveyor arranged in a generally H-shaped pattern including a firstelongated portion, a second elongated portion parallel to said firstelongated portion, and a transverse portion movable along said first andsecond elongated portions dividing said generally H-shaped pattern intoan active path on one side of said transverse portion and a passive pathon the other side of the transverse portion, and transfer means forconnecting said plurality of active portions to each other, whereby thestorage capacity of said conveyor means can be varied by displacing atleast one of said plurality of transverse portions to alter theproportion between said active path and said passive path in at leastone of said plurality of independent conveyor means.
 2. The variablecapacity storage unit of claim 1 wherein said transfer means comprises acurved conveyor extending from one of said plurality of first elongatedportions to another of said plurality of second elongated portionslocated above said one of said plurality of first elongated portions. 3.The variable capacity storage unit of claim 2 wherein at least a portionof said curved conveyor comprises an extension of one of said pluralityof first elongated portions and said another of said plurality of secondelongated portions.
 4. The variable capacity storage unit of claim 1wherein each of said plurality of transverse portions is independentlydisplaceable along said one of said first and second elongated portionsassociated therewith, whereby the capacity of each of said plurality ofconveyor means is independently controllable.
 5. A variable storagearrangement comprising a first variable capacity storage unit comprisinga first plurality of independent conveyor means connected to operate asa single storage unit, each of said first plurality of independentconveyor means comprising an endless conveyor arranged in a generallyH-shaped pattern including a first elongated portion, a second elongatedportion parallel to said first elongated portion, and a first transverseportion movable along said first and second elongated portions dividingsaid generally H-shaped pattern into an active path on one side of saidfirst transverse portion and a passive path on the other side of saidfirst transverse portion, and first transfer means for connecting saidplurality of active paths to each other, whereby the storage capacity ofsaid first plurality of independent conveyor means can be varied bydisplacing at least one of said first transverse portions to alter theproportion between said active path and said passive path, and a secondvariable capacity storage unit comprising a second plurality ofindependent conveyor means connected to operate as a single storageunit, each of said second plurality of independent conveyor meanscomprising an endless conveyor arranged in a generally H-shaped patternincluding a third elongated portion, a fourth elongated portion parallelto said third elongated portion, and a second transverse portion movablealong said third and fourth elongated portions dividing said generallyH-shaped pattern into an active path on one side of said secondtransverse portion and a passive path along the other side of saidsecond transverse portion, and second transfer means for connecting saidplurality of active paths to each other whereby the storage capacity ofsaid second plurality of independent conveyor means can be varied bydisplacing at least one of said second transverse portions to alter theproportion between said active paths and said passive paths, whereinsaid first variable capacity storage unit is adapted to transport goodsbetween said first plurality of independent conveyor means in a firstdirection, and said second variable capacity storage unit is adapted totransport said goods between said second plurality of independentconveyor means in a second direction opposite to said first direction,said third and fourth elongated portions being positioned between saidfirst and second elongated portions and said second transfer means beingpositioned between said first transfer means and said plurality ofsecond transverse portions whereby said plurality of first independentconveyor means substantially circumvents said plurality of secondindependent conveyor means.
 6. The variable capacity storage unit ofclaim 5 wherein said generally H-shaped patterns of said first variablecapacity storage unit are vertically displaced from said generallyH-shaped patterns of said second variable capacity storage unit.